In one aspect, the invention relates to compositions comprising siloxanyl compounds comprising the structure: or residues thereof. Such compositions can be suitable for producing molded articles, can be excellent in transparency, hydrophilicity, and oxygen permeability, and can have a low modulus of elasticity and/or an excellent optical quality, so as to be suitable for ophthalmic lenses such as contact lenses and intraocular lenses. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.